Ah, you can't use any modifiers above Skin, they generally won't export at all. I'd suggest editing the normals directly above the Editable Poly modifier. Also, the Morpher modifier probably won't transfer under the Skin. This is something you should setup directly in the game engine.
Triangles are usually stored in tri-strips. https://en.wikipedia.org/wiki/Triangle_strip This means the list of vertexes has no idea of a 'face' definition. This is why engines tend to split the vertexes where there's a change in normals or UVs. Although the geo I made for this example isn't very tri-strip friendly :p
Your train engine looks rounder in the concept art. If it isn't a stylistic choice, I think trying to get to work in 3D space would be better. It would contrast nicely with the straight edges and blocky shapes of the cars. I really really like the texture work on this. It's very warm and comfy.
My next move was making the 2 types of chairs that are visible in my mood board, a simple chair and one with more detail and worked wood. I started by making alphas in photoshop so I could add height detail in Substance Painter. And this is what the chairs look like in engine
I was trying to convince of 3dc, but failed. You know how programmers are if they think "its good enough". That, and we have the specs alpha in the normal maps (long story and bleh engine), which Im not sure 3dc would even allow as it is. Results vary. Look fugly to me, but ehh.
There is an issue with xnormal that has turned me off a little. You can see it on this page. http://www.polycount.com/forum/showpost.php?p=1169198&postcount=1984 Max has a way of tweaking edges so the blend better than Xnormal. It doesn't seem to matter the realtime dx render engine.
green is the indicator for missing shader... this could happen if you dont load the render engine plugin... or if maya is loosing the connection just fo fun... reassigning the shader should help... sometimes you need to assign the labert1 shader first and than the right one... or resetting the viewport --> ogs -reset
Lots of studios write viewport shaders to match their engines - maya is more powerful in the regard as you can basically replace the renderer if you want to. It's pretty straightforward to put a shader together for either though. That said... You could probably achieve the results there by simply putting it in fancy mode…
ah yes, nice. could it be tress-FX or an inhouse software essentially doing the same thing? https://en.wikipedia.org/wiki/TressFX i have no experience with it but it seems to allow a mix of cards and strands: https://cdn.wccftech.com/wp-content/uploads/2015/03/Dawn-Engine-4-740x416.jpg
I was talking more about a short 30 second video to accompany a project (placed near the bottom of the images). I was fortunate enough to get a feature in in the Unreal Engine Project Showcase on their live stream back in 2014 and it definitely helped play a role in getting my first position in the industry.